Process of recovering metal from scrap material.



.I. W BROWN, PROCESS OF RECOVERING METAL FROM SCRAP MATERIAL. APPucmouFILED JULY 15. 1914.

1,%0,312. Patented Mar. 26,1918.

JOHN W. BROWN, OF LAKEWOOD, OHIO.

PBOGESS OF BECOVERING METAL FROM SCRAP MATERIAL.

eciflcation of Letters Patent. Patented Mar. 26, 1918.

Application filed July 15, 1914. Serial No. 851,058.

act description.

This invention relates to a process for the recovery of metals fromscrap material containing the metal sou ht. The object of the theworkmen thereto,

invention is to. provi e a process which will obviate certaindifiiculties and objections inherent in present methods employed, anfurther a process which will recover the metal in such form as to becommercially usable and profitable of recovery.

Generally speaking, the invention com-- prises the process steps andcombinations thereof set forth in the claims.

As illustrating one form of apparatus with which my process may beCaITIGdJOHt, reference should be had to the accompanying drawingsforming a part of the specification, in which the apparatus isdiagrammatically illustrated in elevation.

The recovery from scrap material, such as borings, filings, turnings,clippings, unchings, sawings, etc., of certain meta s and their alloyssuch as zinc, aluminum, etc., has been attempted by melting the scrap ina crucible, rakin or stirring the mass to separate the meta therefromand usually adding a flux to the dross material for the purpose ofrecovering further amounts of metal. a:

- In some cases, the flux or portions thereof may be volatile, whichrepresents a loss of material, as well as causing fumes which areobnoxious and in a measure harmful to manipulating the process.

Further, a large part of the metal usually separates from the mass inthe crucible in the form of small globules which for some reason,possibly because they are surroundof oxid, do not flow together, anditis impossible to use the metal in this small globular form, so that themetal must be removed from the crucible and further treatment given thesame before the globules are united in usable form.

In addition, the flux and skimmings being at the top of the cruciblewith air accessible will at a red heat cause the skimmmgs to burn, attimes with considerable violence, which results in a very appreciableloss of material and a rapid deterioration of the melting pot.

The process of my invention is also applicable to certain condensationIcy-products, such as blue powder and similar material.

In my process, the disadvantages above enumerated are very largelyeliminated and reduced to a minimum, metal is in excess of the yieldobtained by usual methods.

It may be well at this time to explain the apparatus shown in thedrawing.

At 1 is represented a furnace of fire brick or similar material, thefurnace being heated by gas from a burner represented at 2, which may beof any desired construction, as shown. Air is mixed with gas in theburner. There is a flue leading from the furnace at 3.

Mounted to extend within the furnace is a crucible 4 which mayout-turned flanges resting upon the top of the furnace. The crucible mayalso be supported at the bottom thereof by resting upon a pier 1- withinthe furnace.

The crucible is provided with a cover which is split at the middlethereof, there being an opening 5* at the center, the purpose of whichWlll be explained later. The cover is also provided with an opening 5which is adapted to cooperate with a pipe 6 which may be insertedtherein when desired, and supplying .an oxidizing, an inert, or reducinggas to the interior of the crucible, as conditlons may require.

The cover is also provided with an opening 5 which may cooperate withthe pipe 7 in a manner which will be later explained.

At one side of the furnace, right 8 which near its upper end has ahousing 9 slidably mounted thereon, upon which housing is pivoted alever 10. The lever carries a rod 11 upon which is a head 12. I The rods10 and 11 are provided with o enings arrangedin series so that therelat1ve mounting of the rod 11 with respect to the rod 10 may bevaried. The head 12 is usually of flat construction, and of somewhatsmaller diameter than the diameter of the crucible. The head 12 and theparts associated therewith are for the purpose of producing pressureuponthe mass of material, which may be treated within the crucible 4,the cover 5 being removed when this operation is efi'ected.

and the yield of be provided with there is an up- Upon the same upright8 there is an ex tending arm 13 at the outer end of which is mounted ashaft .141, which below the arm is provided with a stirring device 15and above the arm with a worm wheel 16. This worm wheel cooperates witha worm which is driven by a motor 17. The arm 13 is mounted so that itmay be swung upon the upright 8 and is properly positioned, so that itmay be swung above the crucible and lowered into the same. The cover 5,as heretofore stated, is split and the opening will fit around thatportion of the shaft 14 which is immediately above the stirrer 15.

At 18 there is generally represented a fumearresting device. Thiscomprises a lower chamber 19 and an upper chamber 20. The

two chambers are separated by a partition 21 which has a centralopening, above which opening is a spreader 22. The chamber 19 isprovided with an outlet door 19 The chamber 20 has adjacent the'topthereof, a support 23 from which hang a series of strips of fibrousmaterial, represented at 24. These extend substantially to the bottom ofthe chamber. A pipe 25 connects the lower part of the chamber with theupper partthereof, and in this'pipe line, there 1s apump 26 so thatliquid material may be pumped from the bottom of the chamber to the upper'part thereof. As the materialis pumped through the pipe 25 anddischarges upon the support 23, it will, of course, spread over thissupport, and the arrangement is such that the liquid will flow down thefibrous strips 24, and the lower ends of the fibrous strips beingimmersed in the body of liquid at the lower part of the chamber 20, willalso by capillary attraction assist in keeping the strips 24 saturatedwith the solution employed.

The construction just described is but one of a number which may besuccessfully used.

- The purpose of the chamber 20 is to afford large surface of contactbetween fumes and condensing liquid.

At the upper portion there is an outlet 27 which may be under suction-toexhaust the air or gases after they have passed through this fumearrester 18.

The outlet-27 ma have a fan 27 ofsuitable type associated therewith, forthe purpose of producing a suction through. the chamber 20 and the partsconnected there with.

At 28 there is represented a separating device which will separate thedust or skimchamber 32. There is an openin 31 in the partition 31 bywhich opening t e chamber 32 is connected with the chamber 39. In theopening 31 there is a fan 31. The fan shown is simply indicative of anysuitable suction device which will place the chamber 29 under suctionand expel air through the openings 33. In the top of the chamber 32 area series of openings represented at 33, and for each opening 33 is a bag34 through which the air escaping from the chamber 32 -must pass, thebags acting as a sieve to re- ,move fine particles. The bags may besupported in any desired manner.

The suction member 7 is provided with a handle 7 a and the tube of thesuction member 7 is connected by means of a flexible hose 35 with a pipe36. This pipe has a-branch connection 37 which connects with the chamber19 of the fume arrester, while the main extension of the pipe 36connects with the chamber 29 of the separator 28. Valves 38 and 39 areconnected in pipes 37 and 36 respectively, so that the passage of air orgas and other materials through these pipes may be regulated.

In. carrying out the process, the scrap material in the form heretoforementioned is placed within the crucible 4, and the crucible same 'isheated, anduntil the metal is in a soft condition, at which time thecover 5 is removed, and the compressor 12 is lowered into the crucibleand applied on different portions of the surface of the 'mass within thesame.

After this pressure has been applied through a short interval of time,the presser '12 is removed and the cover 5 is replaced. 'The heating isthen continued until substantially the whole mass within the cruciblehas attained a melted or softened condition, at which time the cruciblecover is again removed and the presser 12 broughtinto cons tact with thesurface of the mass within the crucible. At this time, considerably morepressure is exerted upon the mass and the presser is moved to besuccessively brought into contact with different portions of the masswithin the crucible. This pressure squeezes out the metal from the masswithin the crucible and pushes the refractory dross material down to thebottom, so that it occupies a position which may be represented as belowthe line 39 in the figure, while the metal will be above the positionoccupied by the dross. The pressure thus applied also causes the unionof the partielse of metal as they are squeezed from the mass ofm'aterialjtreated, so that the metal may be said to be in massive. formrather than in. divided globular condition.

At this time, the metal 'is removed, the dross broken up and mixed witha flux of suitable material. The stirrer 15 is then positioned to bewithin the crucible, the cover 5 replaced, and the suction nozzle 7 isintroduced through the openmg 5. W1th the stirrer in operation and thecrucible under heat, the flux becomes thoroughly mixed with the drossmaterial, and by the presence of the flux, the dross material is soacted upon that practically all included metal Wlll be released.

The stirring is continued until all the metal is separated from thedross and the fluxing action has ceased. I

This operation of stirring 1n the flux 1s carried onwith the cover inplace upon the crucible. Therefore, it is possible to control thecharacter of the atmosphere above the bath. That is to say, it may bereduclng or oxidizing to any desired degree, for by means of the nozzle16, any character of gas may be introduced. 7

This is an important factor in economical treatment of metal, for ifthere be no control and the air have free access to the surface of thebath in the pot, an excess of oxygen will be present and so burnportions of the metal, which of course means loss. Furthermore, withexcess of oxygen prescut, the surface action is very violent.

All of these undesirable features are eliminated by the control of theoxygen at the surface of the metal in the crucible.

If desired, this heating of flux and dross may be carried on in thepresence of an inert or reducing gas.

The. valve 38 will duringthis operation be opened and the fumesoccasioned by the use of the flux within the crucible will be drawnthrough the nozzle 7, pipe 36 and pipe 37 to the fume arrester 18. Inthe chamber 19 of the fume arrester, the heavier particles of fiux whichmay have come over with the fumes will settle in the lower part of thechamber 19, while those portions carried by the gas or air will passinto the chamber 20 and into contact with the wet strips 24, whichstrips may be wet with water or any other suitable solution which willremove the material that will be carriedin the fumes, so that the gas orair in passing through the opening 27, will be practically free fromobnoxious odors or materials. The flux recovered in the chamber 19 maybe used over again. 7

After the agitation of the mixture within the crucible as justdescribed, the nozzle 7 may belowered into the crucible sufiiciently farso as to remove by suction the dross or oxid which is light in weight,and which of course will form in this instance above the metal becauseno pressure has been applied. The dross will carry some'portions ofincluded metal, and as this dross passes through nozzle 7 and pipe 36 tothe separator 28, the heavier particles will drop to the bottom of thechamber 29, from whence they may be removed, and may be separated or" ifdesired, the material may be mixed with fresh supplies of scrap materialand again subjected to the process. The lighter materials Will pass tothe chamber 32 and be collected therein through the instrumentality ofthe bags 3-1.

During the last mentioned operation, the valve 38 will be closed and thevalve 39 opened.

The metal left in the melting pot may be poured out, if of sufficientquantity, and if not, it may be left, and a fresh/quantity of scrapmaterial added.

It will be apparent that the apparatus described is but one form whichmay be used in carrying out my process, and it is not my intention tolimit the process in any way by the apparatus disclosed.

' Where in the specification, I have used the term scrap material, Iintend to include scrapings, borings, turnings, clippings,

punchings, sawings, etc., of the metal or an alloy of the metal which itis sought to recover.

Having thus described my invention, what I claim is:

1. The process of recovering a metal from scrap material which whenmelted forms distinct and separate bodies of metal which consists inheating the scrap material to or above the temperature at which itsoftens or melts, and applying pressure to the mass of material to unitethe separated bodies of metal into a unitary mass.

2. The process of recovering a metal from scrap material which whenmelted forms distinct and separate bodies of metal which above thetemperature at which it softens or melts, in which condition the metalis in separated particles or globules, and apply I ing pressure to themass of material to squeeze the metal particles into a unitary mass andseparate them from the dross.

1. The process of recovering a metal from scrap material which whenmelted forms distinct and separate bodiessof metal which consists inheating the scrap material to or above the temperature at which itsoftens or melts, in which condition the metal is in the form ofglobules surrounded by a coating of dross which prevents their union,and applying pressure to the mass of material to squeeze the metalparticles into a material in the fumes, and removing the unitary massand separate the same from the dross.

5. The process of recovering a metal from squeezing out the metal fromthe mass andpushing the dross below the metal, in removing the metal,mixing a flux with the dross, and stirring and heating the same.

6. The process of recovering a metal from scrap material which consistsin heating the scrap material to a softened condition, compacting themetal and separating it from the dross, removing the metal, mixing aflux with the dross, stirring and heating the same, and by suctionremoving the fumes as the mass of material is heated, and recoveringmaterial in the fumes.

7. The process of recovering'metal from scrap material which consists inheating the said material to a softened condition, compacting the metaland separating it from the dross, removing the metal, mixing a flux withthe. dross, heating the same, by suction removing the volatilized matterand fumes, and recovering the material in the fumes, and also by suctionremoving the dross and recovering the particles of metal therein.

8. In a process for recovering metal from scrap material, heating thescrap material and removing the metal from the dross,

heating the said dross with the flux, remov ing the fumes by suction andrecovering the dross by suction and recovering the metal particles inthe dross;

9. In a process for recovering metal fr m scrap material which consistsin heating t e scrap material and separating the metal from the dross,treating the dross with a flux, heating the same, and removing the drossby suction and separating the metal particles therefrom.

10. In a process for recovering metal from scrap material which consistsin heating the scrap material and separating the metal from the dross,treating the dross with a flux, heating the same in an atmospherecontrolled to prevent excessive oxidization, and removing the dross bysuction andseparating the metal particles therefrom.

11. The process of recovering metal from scrap material which consistsin heating the said material to a softened condition, oompacting themetal and separating it from the, dross, removing the metal, mixing aflux with the dross, heating the same in an atmosphere controlled toprevent excessive oxidization, by suction removing the volatilizedmatter and fumes, and recovering the material in the fumes, and also bysuction removing the dross and recovering the par ticles of metaltherein.

In testimony whereof, I hereunto afli-x my l signature in the presenceof two witnesses.

7 JOHN W. BROWN. Witnesses:

A. J. HUDSON, 'L. I. PORTER.

